Note: Descriptions are shown in the official language in which they were submitted.
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RADIO RECEIVER FOR DIGITAL AUDIO BROADCASTS INCLUDING
MESSAGES AS WELL AS RADIO PROGRAMS
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a radio receiver
for digital radio broadcasts (Digital Audio Broadcasts or
DAB broadcasts) with at least one loudspeaker output, and,
more particularly, to a digital radio receiver for
simultaneous reception of priority digital messages and
radio programs.
2. Prior Art
Digital radio broadcasting or also "Digital Audio
Broadcasting", abbreviated DAB, is a new type of
broadcasting of wireless radio programs. The radio programs
are no longer broadcast, as is common up to now in VHF
broadcasting, as analog signals modulated on a carrier
signal, but are transmitted in digital form. A conventional
radio receiver, for example an auto radio, however cannot
convert this new form of broadcast radiation or waves into a
program that can be heard by a user. Instead new receiving
equipment designed for this form of transmission is required
that is designated as a "DAB receiver" or "radio receiver
for DAB broadcasts".
In a corresponding manner as with Radio-Data-
Systems (RDS) for the currently conventional analog radio
broadcasts in the VHF band, different types of message or
information signals for DAB are defined, for example traffic
message signals. In the current analog RDS system radio
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transmitters are provided with RDS and traffic messages are
indicated in a signal device of the radio receiver with "TP"
(Traffic Program/Radio Program with traffic information). This
indicates to the user that the instant radio transmitter
offers this service. A "TA" (Traffic Announcement/traffic
messages) key activates RDS operation and the "TA" signal
appears in the signal device and signals the user that the RDS
or the traffic message system is active.
An RDS message signal, such as a traffic message
signal, interrupts the program that is currently being trans-
mitted from the radio transmitter to the RDS radio receiver in
each case. A radio program with RDS message signals only
needs to be monitored by the user during, for example, the
playing of a CD or a music cassette in the background. When a
message signal is detected the radio program is switched to
the loudspeaker outputs momentarily interrupting the playing
of the CD or music cassette so that the user can actually hear
the actual traffic message. Similarly a user can temporarily
mute the radio program and have the RDS radio receiver
automatically unmute the radio program when a traffic signal
is identified as being present in it.
However this current analog RDS system has the
disadvantage that traffic message signals are only available
at a predetermined time, namely when they are broadcast. In
contrast, necessarily no traffic message signals are available
immediately prior to the initial travel of the motor vehicle.
However it is at this time that the first decisions regarding
the travel route are made and an actual traffic information at
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this time could be of significant value as an aid to making
such decisions.
In the new DAB system different types of message
signals, subsequently also designated as DAB message signals,
do not interrupt programs being broadcast, but are broadcast
in parallel data channels that are parallel to the running
program according to the digital character of the broadcast.
In other words, the different signals arrive without
interruption of a running program, If the user would like to
hear the actual current new DAB message signal, he or she can
activate a suitable function in the DAB receiver so that the
detected DAB signals can be heard immediately temporarily
interrupting the current radio program. The user can also
choose whether he or she hears the current radio program
without interruption or whether he or she hears the actual DAB
message signals during a suitable program interruption.
According to ETS 300 401 however additionally besides the
conventional advisory signals "alarm", "traffic message",
"news" and "weather advisory", as already defined in the RDS-
system, also "public conveyance messages", "warning", "event
information" and "special message" are defined. Besides these
eight already defined DAB message signal types at least eight
other distinct information signal types are possible, but have
not up to now been defined or used. For the user this creates
the problem that he or she either hears all the information
signal types or none. This is however unsatisfactory, since
he or she is, for example, only interested in traffic
information, however not event information.
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Summary of the Invention
It is an object of embodiments of the present
invention to provide an improved radio receiver for DAB
broadcasts of the above-described type that eliminates the
above-described disadvantage and allows the user to use the
DAB message or information signal types in a more
comfortable and efficient manner.
According to one aspect of the invention, there is
provided a radio receiver for DAB broadcasts including a
radio program and message signals of different types, said
radio receiver having a current state, and comprising: at
least one loudspeaker output; a message filter device
comprising means for conveying only predetermined types of
said message signals to the at least one loudspeaker output,
means for interrupting said current state so that said
predetermined types of said message signals conveyed to the
at least one loudspeaker output by the means for conveying
are made audible during an interruption of the current
state, and means for suppressing remaining ones of said
message signals so that said current state is not affected;
and means for controlling the message filter device
including means for receiving inputs from a user selecting
the predetermined types of said message signals, wherein an
attribute is assigned to the selected predetermined message
types, with which it is determined whether a message type
should be suppressed or should interrupt the current state.
The radio receiver according to one embodiment of
the invention has the advantage that a user can determine
which DAB messages interrupt the programs he is currently
hearing in the receiver's current state, in which the user
is listening to a radio program or recorded music produced
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from a CD or tape cassette, and can suppress the other
remaining DAB messages.
There are several preferred embodiments of the
invention set forth in the dependent claims appended herein-
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below.
A single message program key can be provided for
simple and convenient operation, which activates or
deactivates the message filter device according to choice in a
predetermined manner by a first predetermined operation, which
preferably is a comparatively brief or short pressing of the
message program key, for example for a second or less.
An individual selection of the predetermined message
types can be initiated by a second predetermined operation of
the message program key in which the radio receiver is
switched into a configuration mode in which the message types
to be suppressed and those to be conveyed to the at least one
loudspeaker output are selected. Advantageously the second
predetermined operation of the message program key is a
comparatively longer pressing of the message program key, for
example longer than one second.
In the preferred embodiments the preferred message
types include "alarm messages", "traffic messages", "messages
regarding public conveyances", "warnings", "news", "weather
advisories", "event messages" and "special messages".
In a preferred embodiment of the radio receiver of
the invention the momentary or current state of the radio
receiver is a receiver state in which a radio program or
recorded music, for example from a CD or a cassette, is made
audible for the user, by means of a loudspeaker output or
outputs and/or a muting circuit of the radio receiver.
Brief Description of the Drawing
The objects, features and advantages of the
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invention will now be illustrated in more detail with the aid
of the following description of the preferred embodiments,
with reference to the accompanying sole figure which is a
block diagram of a preferred embodiment of a radio receiver
for digital audio broadcast waves according to the invention.
Description of the Preferred Embodiments
The preferred embodiment of a radio receiver 100 for
digital audio broadcast waves according to the invention shown
in the sole figure comprises a receiver section 12 with an
unshown input filter, demodulator, D/A converter and suitable
NF processor. An evaluation of the different data channels of
the received signals occurs in the receiver section 12. The
signal of the data channel with the radio program is conveyed
into the amplifier 14 as NF with a basic adjustment and is
made audible to the user by means of the loudspeaker output 16
and the loudspeaker 18.
A signalling device 20 connected with the receiver
section 12 provides the user with different information, such
as the currently tuned reception frequency. Control keys 24
and 26 for controlling the receiver section 12 are provided in
a control section 22.
A message filter device 28 continuously tests the
appropriate data channels of the received signal for DAB
message signals, such as "alarm", "traffic information",
"news", "weather advisory", "public traffic agent", "warning",
"event information" and "special message". If a message is
detected, according to the mode set by the control section the
message is ignored or the receiver section 12 is controlled so
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that the DAB message is conducted from the message filter
device 28, for example by means of cable or line 34, to the NF
amplifier 14 instead of the running program.
The message filter device 28 can also be integrated
in the receiver section 12 or arranged in the signal path
between the antenna 10 and the loudspeaker 18.
For example, four modes for analysis or evaluation
of the message types are provided:
In a first mode the DAB messages are ignored.
However an information signal appears in the signalling device
in this mode that indicates the types of information
present in the signal which the receiver section is currently
receiving. No signals of any type means e.g. that no DAB
messages are supported. A signal "TP" means that DAB traffic
messages were transmitted, but no other messages. A signal
"TP+" means that other signals in addition to the traffic
message were transmitted and these can be filtered selectively
by means of the message filter 28 as desired or not. A signal
"P+" means for example that traffic signals are not supported
20 however other messages are.
In a second mode all detected traffic messages and
only the traffic messages are delivered during an inter-
ruption of the currently running program at the loudspeaker
output 16. This second mode is, for example, indicated as
"TA" at the signalling device 20. This signal indicates an
exclusive active support of only the traffic messages.
In a third mode only certain predetermined types of
DAB message signals besides the traffic signals are delivered
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to the loudspeaker output 16 during an interruption of the
currently running program. This third mode is indicated in
the signalling device 20 for example with "TA+ . This signal
indicates then an active support of traffic messages and at
least one additional message type, which however is not
directly known in this embodiment. This message type is set
in the message filter, as explained in more detail in the
following description.
In a fourth mode only predetermined DAB message
signals are delivered to the loudspeaker output 16 during an
interruption of the currently running program and traffic
messages are counted among the suppressed DAB message signals.
This fourth mode is indicated for example with "A+" in the
signalling device. This signal indicates thus the
deactivation of the support for the traffic messages, however
at least one other message is actively supported. This is set
by means of the message filter device.
For example, a brief operation of the message
program key 24, which is indicated preferably the "TA+",
operation of the receiver can be switched between these modes.
A push button operation of the functions of the message filter
device 28 is thus possible by means of this message program
key 24. The message types may be controlled with this key 24
"TA+", i.e. activating, deactivating, active message
interruption, etc. and also a function-related menu can be
retrieved by pressing the key for a longer time, for example
longer than 1 second.
In a menu of this type individual attributes of
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those message types that should be suppressed and those
message types that should be delivered to the loudspeaker
output during an interruption of a running program may be set.
For example the following attributes are provided:
"OFF": The running radio program is not interrupted
if the message type has this attribute.
"ON": When the selected program supports message
types with this attribute, these message types are switched to
loudspeaker output 16 during an interruption of the running '
radio program. However program broadcasts that do not support
these message types are received and offered during automatic
program operation.
PS": is like "ON" however only those program
broadcasts are offered which support these message types
during automatic program operation.
The calling up of the selection menu for determining
the named attributes occurs, for example, by pressing the
"TA+" key 24 for a comparatively longer time, for example
longer than one second. Then the different message types are
shown on the signalling device 20 and are selectable by means
of the up/down key 30. The attribute of a selected message
type is selected by successively repeatedly pressing the
front/back key 32 so that the attribute is changed from one
attribute, i.e. from "OFF", "ON" or "PS", to the next
attribute each time the key is pressed. When all the
attributes for the different message types are selected, the
"TA+" key 24 is pressed again to make this mode configuration
final and the actual set up according to the selected
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attributes is activated.
The message filter is equipped further in a
preferred manner so that on detecting a message of the type
provided with the "ON" attribute a muting circuit of the
receiver is activated to interrupt the running program and the
actual message is conducted to the loudspeaker output 16.
The message filter thus takes different states.
These different states in the present embodiment are indicated
only with "OFF", "ON" or "PS". "ON" means that the special
message with this attribute is conveyed through the message
filter. "PS" means that the filtering is broadened, since
only those programs are selected during program changes that
support the message types designated as "PS" types. "OFF"
indicates that the filter is not active for these message
types, i.e. messages of this type are ignored and are not
passed through the filter.
A necessarily supported alarm message takes a
special position. This message is always switched active in
the special case of a mobile receiver, i.e. indicated as "ON"
in the message filter, and thus is not manually selectable
during set up of the message filter. Correspondingly it is
not considered with the other signals of "empty", "TA","TA+
and "A+".
In a special embodiment the radio receiver according
to the invention also includes an RDS(Radio Data System)
receiving section and can selectively process an analog
FM-signal with an RDS-signal or a digital signal with DAB
broadcasts, according to which signal would provide the
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optimum instant reception, wherein a digital signal is given
priority as much as possible.
The expression "radio broadcast" used here is not
limited to wireless transmission of a radio program, but
includes other transmission media, such as cable
transmission or the like.
The instant selected filter mode of the message
filter device processes the preferred message types of the
currently selected radio programs received by the receiver.
These messages can be transmitted with the radio signal
itself or for example also in an additional channel. In a
preferred embodiment the message filter monitors also other
radio transmission channels not currently being received,
conveys their messages in its radio signal or in an
additional channel and conveys these messages to the
loudspeaker outputs if the messages received have an "ON"
attribute.
While the invention has been illustrated and
described as embodied in a radio receiver for digital audio
broadcasts including radio programs and messages, it is not
intended to be limited to the details shown, since various
modifications and changes may be made without departing in
any way from the spirit of the present invention.
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Without further analysis, the foregoing will so
fully reveal the gist of the present invention that others
can, by applying current knowledge, readily adapt it for
various applications without omitting features that, from the
standpoint of prior art, fairly constitute essential
characteristics of the generic or specific aspects of this
invention.
What is claimed is new and is set forth in the
following appended claims.
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